1. Field of the Invention
The present invention relates to an input device. More particularly, the input device of the present invention determines a relative position of an object with respect to a top surface of a light guide plate by sensing a light reflected by the object on the top surface of the light guide plate.
2. Descriptions of the Related Art
With development of the computer industry, providing well-designed peripheral input devices has become a goal of all manufacturers. Mice and touch panels are the most common input devices for controlling a pointer of an operation system.
A conventional mouse is usually provided with a wheel for scrolling a picture displayed by the operation system or for controlling other operations of the operation system. However, the wheel of the mouse is prone to malfunctions due to oxidation of a micro-switch thereof or abrasion of a bearing thereof during use. On the other hand, a conventional capacitive touch panel tends to become insensitive due to environmental factors (e.g., humidity) during use.
Accordingly, an urgent need exists in the art to provide an input device to avoid the problems with the conventional mice and the conventional capacitive touch panels during use.